1. Field of the Invention
Many crude oils are lighter than water, particularly sea water; and hence crude oils tend to float when a tanker has its liquid-tight integrity impaired by a storm, an accident, an act of man, or otherwise. That crude oil can be highly objectionable in an ecological sense, in an economic sense, and in a recreational sense. Consequently, it would be desirable to construct ships which would minimize the loss of crude oil or other lighter-than-water fluids in the event the liquid-tight integrity thereof was impaired. 2. Description of the Prior Art
Wells U.S. Pat. No. 3,556,036 discloses a Deep Sea Cargo Vessel which is submerged so large cargo barges can be floated into position above it; and those cargo barges are supposed to be "firmly seated on the cargo deck" as that "vessel is resurfaced".
Cushing et al U.S. Pat. No. 3,823,681 discloses a Barge Carrying Transport Vessel which is submerged so barges can be floated into position above it; and those barges are supposed to be held in position within that vessel by tapered male pins 55 and corresponding female apertures 56.
Mikk U.S. Pat. No. 3,672,320 discloses a Ship For Containerized Cargo wherein "a plurality of vertically extending receptacles 13" accommodate "removably placed containers 14 containing oil or the like. **A plurality of latches 19 may be positioned at the upper end of the oil tank container so as to secure the same within the compartment. Below the oil tank container there is positioned an ejection mechanism 20**. A water level sensor 21 for activating the ejection mechanism 20 is located within the compartment 13 near a lower end thereof.**"